Built in aMule file hash checker integrated with search and shared window comparing to known database.
So for example let say you go to
http://donkeyfakes.net and download there fakes.dat or similar database just like ipfilter.dat you will load the file fakes.dat when aMule starts. When you search something the returned result will be compared to the known hash of the database if match it will show in a selected color let say red to warn users that its a fake file or could have a notation of something to easily identify it. Also if user is sharing any files that match the fakes.dat known hash's it will show up red in shared file so user can see it and unshare/delete or whatever action they take.
If an entry is not shown in the fakes.dat and user verified the file as corrupted, fake, ect then they should have a userfakes.dat which will add any entry by click and blacklist the file hash thats not already in fakes.dat this way user won't download the same fake files as you can make this color black so user knows they blacklisted the file. If they chose then they can also go to donkeyfakes and submit their finding and they may add it to global fakes.dat so everyone can use it.
PS: I don't download much via aMule from eD2k/KAD as I mainly share on it. But I am sure for those who do download alot can find this simple thing very helpful now I am not sure if eMule have this already or can't say as I never used eMule. If eMule don't have it then aMule can start it then they might adopt it this way eD2k can be cleaned up slowly. So whatever comment on it as you like freely add idea take away whatever I am sure this wont be added lol as most good idea never is but this along with ipfilter.dat, good server.met can be helpful in my view.